Combined sustainable sanitising treatments to reduce Escherichia coli and Salmonella Enteritidis growth on fresh-cut kailan-hybrid broccoli

The effects of peroxyacetic acid (PA), neutral electrolysed water (NEW), ultraviolet C light (UV-C) and superatmospheric O2 packaging (HO), single or combined, on the growth rate of Escherichia coli and S. Enteritidis inoculated onto fresh-cut kailan-hybrid broccoli were studied throughout 14 days of shelf life at 5 and 10°C. As controls, unwashed, water-washed and NaClO-washed were used. PA and NEW showed a better sanitising effect than NaClO against both E.coli/S. Enteritidis with reductions of 2.2/2.7 and 2.6/2.6logCFUg-1, respectively. UV-C attained E.coli/S. Enteritidis decreases of 1.3-1.4/2.1-2.2logCFUg-1 compared to unwashed samples. The bacteriostatic effects of PA or NEW were improved when they were combined with UV-C, decreasing E.coli and S. Enteritidis counts by about 3logCFUg-1. After 14 days, PA and NEW-treated samples attained E.coli/S. Enteritidis reductions at 5°C of 2.3/1.4 and about 1logCFUg-1, respectively. Storage of those samples at 10°C masked that sanitising effect. At both storage temperatures, UV-C-treated samples registered lower E.coli and S. Enteritidis reductions (or higher increases for S. Enteritidis at 10°C) regarding conventional NaClO-sanitized samples or other single treatments. However, PA, NEW or UV-C-treated samples under HO at both storage temperatures showed better bacterial control than individual treatments with the greatest effectiveness for UV-C+HO. Triple combination did not imply an enhanced benefit over double combinations. Conclusively, PA, NEW and UV-C seems to be effective emergent alternatives to NaClO to reduce initial E.coli and S. Enteritidis populations in fresh-cut kailan-hybrid broccoli. Storage at 5 or 10°C under HO greatly controlled microbial growth. © 2014 Elsevier Ltd.